double syten::full_rank_ness | ( | DenseTensor< 2, std::complex< double > > && | a | ) |
Estimates the full-rank-ness of a complex matrix A (compared to its smaller dimension) using QR with pivoting.
Does not perform row sorting or row pivoting. For optimal stability, you should do both, using scale_columns_2norm
and sort_rows_infnorm
.
Returns the ratio of largest to smallest (absolute-value-wise) diagonal element of R. A ratio of 1 indicates an identity matrix, a very large ratio a near-degenerate matrix and a value of inf
a matrix not of full rank.
References abs(), syten::DynArray< Type >::begin(), syten::DynArray< Type >::end(), logGE(), std::min(), syten::DynArray< Type >::size(), and std::sort().
Referenced by full_rank_ness().